This invention relates to nonsteroidal tetracyclic compounds that are modulators (i.e. agonists and antagonists) of progesterone receptors, and to methods for the making and use of such compounds.
Progesterone receptor (PR) modulators have been widely used in regulation of female reproduction systems and in treatment of female hormone dependent diseases. The effectiveness of known steroidal PR modulators is often tempered by their undesired side-effect profile, particularly during long-term administration. For example, the effectiveness of synthetic progestins, such as norgestrel, as female birth control agents must be weighed against the increased risk of breast cancer and heart disease to women taking such agents. Similarly, the progesterone antagonist, mifepristone (RU486), if administered for chronic indications, such as uterine fibroids, endometriosis and certain hormone-dependent cancers, could cause homeostatic imbalances in a patient due to its inherent cross-reactivity as a glucocorticoid receptor (GR) antagonist. Accordingly, identification of compounds that have good specificity for PR, but have reduced or no cross-reactivity for other steroid receptors, would be of significant value in the improvement of women""s health.
Nonsteroidal molecules that contain a di- or tetrahydroquinoline ring as the core pharmacophore have been described as steroid receptor modulator compounds. {See for example: xe2x80x9cPreparation of Quinolines and Fused Quinolines as Steroid Receptor Modulatorsxe2x80x9d, T. K. Jones, M. E. Goldman, C. L. F. Pooley, D. T. Winn, J. P. Edwards, S. J. West, C. M. Tegley, L. Zhi, L. G. Hamann, R. L. Davis, L. J. Farmer, PCT Int. Appl. Pub. No. WO 96/19458; xe2x80x9cSteroid Receptor Modulator Compounds and Methodsxe2x80x9d, T. K Jones, D. T. Winr, L. Zhi, L. G. Hamann, C. M. Tegley, C. L. F. Pooley, U.S. Pat. No. 5,688,808; xe2x80x9cSteroid Receptor Modulator Compounds and Methodsxe2x80x9d, T. K Jones, M. E. Goldman, C. L. F. Pooley, D. T. Winn, J. P. Edwards, S. J. West, C. M. Tegley, L. Zhi, U.S. Pat. No. 5,688,810; xe2x80x9cSteroid Receptor Modulator Compounds and Methodsxe2x80x9d, T. K Jones, C. M. Tegley, L. Zhi, J. P. Edwards, S. J. West, U.S. Pat. No. 5,693,646; xe2x80x9cSteroid Receptor Modulator Compounds and Methodsxe2x80x9d, T. K Jones, L. Zhi, C. M. Tegley, D. T. Winn, L. G. Hamann, J. P. Edwards, S. J. West, U.S. Pat. No. 5,693,647; xe2x80x9cSteroid Receptor Modulator Compounds and Methodsxe2x80x9d, T. K Jones, L. Zhi, J. P. Edwards, C. M. Tegley, S. J. West, U.S. Pat. No. 5,696,127; xe2x80x9cSteroid Receptor Modulator Comnpounds and Methodsxe2x80x9d, T. K Jones, D. T. Winn, M. E. Goldman, L. G. Hamann, L. Zhi, L. J. Farmer, R. L. Davis, U.S. Pat. No. 5,696,130; xe2x80x9cSteroid Receptor Modulator Compounds and Methodsxe2x80x9d, T. K Jones, M. E. Goldman, C. L. F. Pooley, D. T. Winn, J. P. Edwards, S. J. West, C. M. Tegley, L. Zhi, L. G. Hamann, L. J. Farmer, R. L. Davis, U.S. Pat. No. 5,696,133.} Molecules containing a bicyclic heterocycle have been reported as cardiotonic agents. {See: xe2x80x9cA Novel Class of Cardiotonic Agents: Synthesis and Biological Evaluation of 5-Substituted 3,6-Dihydrothiadiazin-2-ones with Cyclic AMP Phosphoidesterase Inhibiting and Myofibrillar Calcium Sensitizing Propertiesxe2x80x9d, M.-C. Forest, P. Lahouratate, M. Martin, G. Nadler, M. J. Quiniou, R G. Zimmermann, J. Med. Chem. 35 (1992) 163-172; xe2x80x9cHeteroatom Analogues of Bemoradan: Chemistry and Cardiotonic Activity of 1,4-Benzothiazinylpyridazinonesxe2x80x9d, D. W. Combs, M. S. Rampulla, J. P. Demers, R. Falotico, J. B. Moore, J. Med. Chem., 35 (1992) 172-176.}
The present invention is directed to compounds, pharmaceutical compositions, and methods for modulating processes mediated by PR. More particularly, the invention relates to nonsteroidal compounds and compositions that are high affinity, high specificity agonists, partial agonists (i.e., partial activators and/or tissue-specific activators) and antagonists for progesterone receptors. Also provided are methods of making such compounds and pharmaceutical compositions, as well as critical intermediates used in their synthesis.
These and various other advantages and features of novelty that characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof However, for a better understanding of the invention, its advantages, and objects obtained by its use, reference should be had to the accompanying descriptive matter, in which preferred embodiments of the invention are described.
As used herein, the following terms are defined with the following meanings, unless explicitly stated otherwise.
The terms alkyl, alkenyl, alkynyl and allyl include optionally substituted straight-chain, branched-chain, cyclic, saturated and/or unsaturated structures, and combinations thereof.
The term haloalkyl refers to alkyl structures, including straight-chain, branched-chain, or cyclic structures, or combinations thereof, that are substituted with one or more fluorines, chlorines, bromines or iodines, or combinations thereof.
The term heteroalkyl includes straight-chain, branched-chain, cyclic, saturated and/or unsaturated structures, or combinations thereof, in which one or more skeletal atoms is oxygen, nitrogen, sulfur, or combinations thereof.
The term aryl refers to an optionally substituted six-membered aromatic ring.
The term heteroaryl refers to an optionally substituted, aromatic five-membered heterocyclic ring containing one or more heteroatoms selected from the group consisting of oxygen, nitrogen and sulfur, or to an optionally substituted, aromatic six-membered heterocyclic ring containing one or more nitrogens.
The substituents of an xe2x80x9coptionally substitutedxe2x80x9d structure include, but are not limited to, one or mnore of the following preferred substitutents: F, Cl, Br, I, CN, NO2, NH2, NCH3, OH, OCH3, OCF3, CH3, CF3.
Compounds of the present invention are defined as those having the formula: 
wherein:
R1 through R6 are independently hydrogen, F, Cl, Br, I, NO2, CN, OR10, NR10R11, SR10, COR12, CO2R12, CONR10OR11, optionally substituted C1 to C6 alkyl or heteroalkyl, C1 to C6 haloalkyl, optionally substituted C3 to C8 cycloalyl, optionally substituted C2 to C6 alkenyl or allynyl, optionally substituted allyl, optionally substituted aryl or heteroaryl, or optionally substituted arylmethyl, where R10 and R11 are independently hydrogen, C1 to C6 alkyl or heteroalkyl or haloalkyl, aryl, heteroaryl, optionally substituted allyl, optionally substituted arylmethyl, COR13, SO2R13 or S(O)R13, where R12 is hydrogen, C1 to C6 aLkyl or heteroalkyl or haloalkyl, aryl, heteroaryl, optionally substituted allyl or optionally substituted arylmethyl, where R13 is hydrogen, C1 to C6 alkyl or haloalkyl, aryl, heteroaryl, optionally substituted allyl or optionally substituted arylmethyl;
R7 is hydrogen, C1 to C6 alkyl or haloalkyl or heteroalkyl, aryl, arylmethyl, heteroaryl, COR12, CO2R12, SO2R12, S(O)R12 or CONR10R11, where R10-12 have the same definitions given above;
R8 and R9 are independently hydrogen, C1 to C6 alkyl or haloalkyl or heteroalkyl, optionally substituted C2 to C6 alkenyl or alkynyl, optionally substituted allyl, optionally substituted arylmethyl, optionally substituted aryl or optionally substituted heteroaryl;
X is OCH2, SCH2, NHCH2, OC(O), SC(O), NHC(O), CH2O, CH2S, CH2NH, C(O)O, C(O)S or C(O)NH;
Y is O, S or NR10, where R10 has the same definition given above; and
Z is O, S, NR14, CR14R15, CR14R15CR16R17, OCR14R15, SCR14R15, CR14R15S, NR14CR15R16, or CR14R15NR16, where R14 through R17 each independently are hydrogen, C1 to C6 alkyl or haloalkyl or heteroalkyl, optionally substituted C2 to C6 alkenyl or alkynyl, optionally substituted allyl, optionally substituted arylmethyl, optionally substituted aryl or optionally substituted heteroaryl;
or a pharmaceutically acceptable salt thereof.
In a preferred aspect, the present invention provides a pharmaceutical composition comprising an effective amount of an progesterone receptor modulating compound of formula I or formula II shown above wherein R1-17, X, Y and Z all have the same definitions as given above.
In a further preferred aspect, the present invention comprises a method of modulating processes mediated by progesterone receptors comprising administering to a patient an effective amount of a compound of formula I or formula II shown above, wherein R1-17, X, Y and Z all have the same definitions as those given above.
Any of the compounds ofthe present invention can be synthesized as pharmaceutically acceptable salts for incorporation into various pharmaceutical compositions. As used herein, pharmaceutically acceptable salts include, but are not limited to, hydrochloric, hydrobrornic, hydroiodic, hydrofluoric, sulfuric, citric, maleic, acetic, lactic, nicotinic, succinic, oxalic, phosphoric, malonic, salicylic, phenylacetic, stearic, pyridine, ammonium, piperazine, diethylamine, nicotinamide, formic, urea, sodium, potassium, calcium, magnesium, zinc, lithium, cinnamic, methylamino, methanesulfonic, picric, tartaric, triethylamino, dimethylamino, and tris(hydroxymethyl)aminomethane. Additional pharmaceutically acceptable salts are known to those skilled in the art.
The PR agonist, partial agonist and antagonist compounds of the present invention are particularly useful for female hormone replacement therapy and as modulators of fertility (e.g., as contraceptives or contragestational agents), either alone or in conjunction with estrogen receptor modulators. The PR missing data are also used in the treatment of dysfunctional uterine bleeding, dysmnenorrhea, endometriosis, leionyomas (uterine fibroids), hot flashes, mood disorders, meningiomas as well as in various hormone-dependent cancers, including, without limitation, cancers of ovaries, breast, endometrium and prostate.
It will be understood by those skilled in the art that while the compounds of the present invention will typically be employed as a selective agonists, partial agonists or antagonists, that there may be instances where a compound with a mixed steroid receptor profile is preferred. For example, use of a PR agonist (e.g., progestin) in female contraception often leads to the undesired effects of increased water retention and acne flare-ups. In this instance, a compound that is primarily a PR agonist, but also displays some androgen receptor (AR) and mineralocorticoid receptor (MR) modulating activity, may prove useful. Specifically, the mixed MR effects would be useful to control water balance in the body, while the AR effects would help to control any acne flare-ups that occur.
Furthermore, it will be understood by those skilled in the art that the compounds of the present invention, including pharmaceutical compositions and formulations containing these compounds, can be used in a wide variety of combination therapies to treat the conditions and diseases described above. Thus, the compounds of the present invention can be used in combination with other hormones and other therapies, including, without limitation, chemotherapeutic agents such as cytostatic and cytotoxic agents, immunological modifiers such as interferons, interleukins, growth hormones and other cytokines, hormone therapies, surgery and radiation therapy.
Representative PR modulator compounds (i.e., agonists, partial agonists and antagonists) according to the present invention include: 7-fluoro-4,4-dimethyl-5H-chromeno[3,4-f-]-1,3-benzo[d]oxazin-2-one (Compound 14); 9-bromo-7-fluoro-4,4-dimethyl-5H-chromeno[3,4-f]-1,3-benzo[d]oxazin-2-one (Compound 20); 7-fluoro-9-formyl-4,4-dimethyl-5H-chromeno[3,4-f]-1,3-benzo[d]oxazin-2-one (Compound 24); 7-fluoro-9-hydroxyiminomethyl-4,4-dimethyl-5H-chromeno[3,4-f]-1,3-benzo[d]oxazin-2-one (Compound 25); 9-cyano-7-fluoro-4,4-dimethyl-5H-chromeno[3,4-f]-1,3-benzo[d]oxazin-2-one (Compound 26).
Compounds of the present invention, comprising classes of heterocyclic nitrogen compounds and their derivatives, can be obtained by routine chemical synthesis by those skilled in the art, for example, by modification of the heterocyclic nitrogen compounds disclosed or by a total synthesis approach.
The sequences of steps to synthesize the compounds of the present invention are shown below in the general schemes. In each of the Schemes the R groups (e.g., R1, R2, etc.) correspond to the specific substitution patterns noted in the Examples. However, it will be understood by those skilled in the art that other functionalities disclosed herein at the indicated positions of compounds of formulas I and II also comprise potential substituents for the analogous positions on the structures within the Schemes. In a further aspect, the present invention provides a novel process for the preparation of the compounds of the present invention. 
The process of Scheme I begins with the preparation of fluoroboronic acid 2 by a literature procedure, in which ortho-lithiation of fluorobenzene 1 with an alkyl lithium reagent, such as n-butyllithium (n-BuLi) or tert-butyllithium, in THF or ether at xe2x88x9278 to xe2x88x9250xc2x0 C. followed by addition of a trialkyl borate, such as trimethyl or triisopropyl borate, at xe2x88x9278xc2x0 C. and acidification with an aqueous acid, such as HCl, provides boronic acid 2. Biaryl compound 4 is prepared by a typical palladium catalyzed coupling reaction of boronic acid 2 and bromobenzoate 3 under aqueous or nonaqueous conditions at ambient temperature. The ester 4 is hydrolyzed under basic conditions, such as THF/MeOH/2N Na2CO3, at ambient temperature, and the resulting carboxylate is heated at elevated temperature in a polar solvent, such as DMF, to generate lactone 5. The nitro-lactone 5 is converted to aminobromo-lactone 6 in a one-pot two-step procedure that involves reduction of the nitro group to an amino group under hydrogen atmosphere (catalyzed by palladium on carbon) followed by bromination with N-bromosuccinimide (NBS) in DMF at room temperature. The isopropenyl group is introduced by a palladium-catalyzed coupling reaction, for example, Suzuki coupling reaction between isopropenylboronic acid and bromo compound 6. The resulting amino compound is then converted to the carbamate 7 by treatment with methyl chloroformate in the presence of 4-dimethylaminopyridine. Removal of the carbonyl group of lactone 7 is completed by stepwise reduction with typical reducing agents such as LiAlH4 and Et3SiH in the presence of a catalytic amount of acid (e.g., TFA) to afford compound 8. The final product 9 is obtained by the treatment of compound 8 with tosic acid (TsOH, p-toluenesulfonic acid) in refluxing dichloroethane (DCE). 
Scheme II describes a four-step, selective D-ring modification procedure, in which reduction of lactone 7 with a reducing agent such as LiBH4 provides diol 10 and then NBS bromination of diol 10 in the presence of a base such as triethylamine followed by a selective methylation and NaH mediated nucleophllic cyclization in DMF affords compound 11. Treatment of compound 11 with more than one equivalent of an acid such as TsOH in refluxing dichloroethane provides compound 12.
Scheme III involves selective D-ring functional group conversion from R1-4 to R7-10 by known substituent group conversions such as converting bromo to aldehyde by metal-halogen exchange followed by nucleophilic addition to DMF, or converting an aldehyde to an oxime by hydroxylamine treatment of the aldehyde, or converting an oxime to a cyano group by treatment of the oxime with thionyl chloride. 
Scheme IV describes the conversion of compound 12 to its cyclic thiocarbamate analogue 13 by Lawesson""s reagent (p-methoxyphenylthionophosphine sulfide dimer).
It will be understood by those skilled in the art that certain modifications can be made to the above-described methods that remain within the scope of the present invention.
The compounds of the present invention also include racemates, stereoisomers and mixtures of said compounds, including isotopically-labeled and radio-labeled compounds. Such isomers can be isolated by standard resolution techniques, including fractional crystallization and chiral colulmn chromatography.
As noted above, any of the PR modulator compounds of the present invention can be combined in a mixture with a pharmaceutically acceptable carrier to provide pharmaceutical compositions useful for treating the biological conditions or disorders noted herein in mammalian, and more preferably, in human patients. The particular carrier employed in these pharmaceutical compositions may take a wide variety of forms depending upon the type of administration desired, e.g., intravenous, oral, topical, suppository or parenteral.
In preparing the compositions in oral liquid dosage forms (e.g., suspensions, elixirs and solutions), typical pharmaceutical media, such as water, glycols, oils, alcohols, flavoring agents, preservatives, coloring agents and the like can be employed. Similarly, when preparing oral solid dosage forms (e.g., powders, tablets and capsules), carriers such as starches, sugars, diluents, granulating agents, lubricants, binders, disintegrating agents and the like will be employed. Due to their ease of administration, tablets and capsules represent the most advantageous oral dosage form for the pharmaceutical compositions of the present invention.
For parenteral administration, the carrier will typically comprise sterile water, although other ingredients that aid in solubility or serve as preservatives may also be included. Furthermore, injectable suspensions may also be prepared, in which case appropriate liquid carriers, suspending agents and the like will be employed.
For topical administration, the compounds of the present invention may be formulated using bland, moisturizing bases, such as ointments or creams. Examples of suitable ointment bases are petrolatum, petrolatum plus volatile silicones, lanolin, and water in oil emulsions such as Eucerin(trademark) (Beiersdorf). Examples of suitable cream bases are Nivea(trademark) Cream (Beiersdorf), cold cream (USP), Purpose Cream(trademark) (Johnson and Johnson), hydrophilic ointment (USP), and Lubriderm(trademark) (Warner-Lambert).
The pharmaceutical compositions and compounds of the present invention will generally be administered in the form of a dosage unit (e.g., tablet, capsule etc.) at from about 1 xcexcg/kg of body weight to about 500 mg/kg of body weight, more preferably from about 10 xcexcg/kg to about 250 mg/kg, and most preferably from about 20 xcexcg/kg to about 100 mg/kg. As recognized by those skilled in the art, the particular quantity of pharmaceutical composition according to the present invention administered to a patient will depend upon a number of factors, including, without limitation, the biological activity desired, the condition of the patient, and tolerance for the drug.
The compounds of this invention also have utility when radio- or isotopically-labeled as ligands for use in assays to determine the presence of PR in a cell background or extract. They are particularly useful due to their ability to selectively activate progesterone receptors, and can therefore be used to determine the presence of such receptors in the presence of other steroid receptors or related intracellular receptors.
Due to the selective specificity of the compounds of this invention for steroid receptors, these compounds can be used to purify samples of steroid receptors in vitro. Such purification can be carried out by mixing samples containing steroid receptors with one or more of the compounds of the present invention so that the compounds bind to the receptors of choice, and then separating out the bound ligand/receptor combination by separation techniques that are known to those of skill in the art. These techniques include column separation, filtration, centrifugation, tagging and physical separation, and antibody complexing, among others.
The compounds and pharmaceutical compositions of the present invention possess a number of advantages over previously identified steroid modulator compounds. For example, the compounds are extremely potent activators of PR, preferably displaying 50% maximal activation of PR at a concentration of less than 100 nM, more preferably at a concentration of less than 50 nM, more preferably yet at a concentration of less than 20 nM or less. Also, the selective compounds of the present invention generally do not display undesired cross-reactivity with other steroid receptors, as is seen with the compound mifepristone (RU486; Roussel Uclaf), a known PR antagonist that displays an undesirable cross reactivity on GR, thereby limiting its use in long-term, chronic administration. In addition, the compounds of the present invention, as small organic molecules, are easier to synthesize, provide greater stability and can be more easily administered in oral dosage forms than other known steroidal compounds.